Transitional image for a portion of a display screen



FIG. 1 is a front view of the first image of a transitional image for a portion of a display screen showing our new design; and,

FIG. 2 is a front view of the second image thereof.

The appearance of the image transitions sequentially between the images shown in FIGS. 1-2. The process or period in which the first image transitions to the other forms no part of the claimed design. The broken line showing of a portion of a display screen, text and numbers in both views, and the rectangle and the area within in FIG. 2, is for illustrative purposes only and forms no part of the claimed design. 

The ornamental design for a transitional image for a portion of a display screen, as shown and described. 